Control methods of this type are generally known.
When rolling strip, it may happen that the rolled strip meanders laterally—with respect to the strip running direction. Meandering of the strip generally has the consequence that the strip is unevenly rolled, as seen in the transverse direction of the strip. The uneven rolling may lead to difficulties in subsequent processing stages (in particular in downstream rolling stands). It is therefore generally attempted to roll the strip in such a way that the center line of the rolling stand and the center line of the strip—as seen in the transverse direction of the strip—coincide (central position).
It is known from JP 07 124 620 A to use suitable measured-value transducers on the left and right sides of the strip to detect the tension prevailing there respectively on the feed and exit sides and to form the difference between the respectively detected tensions on the feed and exit sides. The differences in the tensions are fed to a control device, which on the basis of the differences determines a correcting variable for a displacement of the strip. The correcting variable is output to a correcting element, by means of which the transverse positioning is corrected in the direction of the central position.